11. The mine used a spider pressure plate that makes it resistant to blast overpressure . 12. After an overpressure was required, and a section of tunnel was sealed off. 13. The piston lifts in proportion to the overpressure . 14. In space, there is ( virtually ) no medium for an overpressure wave. 15. They were rebuilt once during its short career, the boiler overpressure being changed. 16. A high pressure relief valve provided overpressure protection to the hydraulic system and relieved at. 17. Besides enhanced penetration capabilities, these overpressure variants offer a flatter trajectory and lessened recoil. 18. This " overpressure profile " is known as an N-wave because of its shape. 19. Excess gas is dumped to the environment through the overpressure valve after the bellows is full. 20. To preserve its outer form, a slight overpressure of about is maintained within the hull.